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This is the first of it's kind objective measurement tool for comparing the bass in movies - it's totally apples-to-apples. (The measurement methodology AND content below 2.5 Stars is at the bottom of this post.)

No longer do you have to rely on some website's review of the bass in a movie. Who can decipher what "aplomb" and "bombastic" and "incredibly deep" and "teeth-rattling" and "room-shuddering" really mean, anyway? Now you don't have to.

The links below will take you to each movie's measurements. If a link doesn't take you to the right measurement, reload the browser by hitting F5 or just click on the address bar and hit "Enter." If you find a bad link, post about it and we'll investigate!

Edit by nube: First post got too long, so I had to move maxmercy's measurements methodology here.

Measurement Methodology:

The Overall Star Rating is an average of the following four categories (each one explained in greater detail below):

1. Level

2. Extension

3. Dynamics

4. Execution

1. Level- This is measured by digitally bass-managing the 5.1 or 7.1 signal. The Level is a composite number, and is calculated by the average of the [1] highest peak in dB (maximum 126dB for 5.1, 128dB for 7.1), [2] the average/RMS dB level of the track (125ms integration time) and [3] the RMS peak level (loudest single 1/8th of a second of the film) in dB. Full modulation of the waveform is considered to be 0dBFS. The ratings are as follows:

5 Stars - >112.5dB composite

4 Stars - >110dB composite

3 Stars - >107.5dB composite

2 Stars - >105dB composite

1 Star - <105dB composite

2. Extension - The same bass-managed digital signal above is analyzed with Spectrum Lab, with Nuttall windowing, and either a 1 second or 2 second integration time (the longer the integration time, the higher the resolution, at the cost of dynamic peaks, but for the extension category, it is a moot point). Extension is determined as the -10dB point from the overall peak of EITHER the Peak (green) or Average (red) trace, whichever is higher. The ratings are as follows:

5 Stars - <10Hz extension

4 Stars - <15Hz extension

3 Stars - <20Hz extension

2 Stars - <25Hz extension

1 Star - >25Hz extension

3. Dynamics - The Overall RMS/Average Level of the track from the Level category is subtracted from the Overall Peak Level of the track from the Level category. The ratings are as follows:

5 Stars - >27.5dB Dynamics

4 Stars - >25dB Dynamics

3 Stars - >22.5dB Dynamics

2 Stars - >20dB Dynamics

1 Star - <20dB Dynamics

4. Execution - This is the only purely Subjective category, and will be decided by a plurality in a poll, with single star increments available to be voted on. Vote what you thought about the LF use in the track, and note any clipping/compression/filtering that took place

Please note that no objective measurement system is perfect. The way the measurement scheme is set up, it will be very difficult to achieve 5 Stars overall, and very few films have done so. How good a movie is to watch has no bearing on how it measures. This is a way to objectively look at the low frequency content of a track without all the subjective "it was awesome" and "seismic" rhetoric from professional reviewers for nearly every BD release.

There will be some films which are LF monsters that will not garner 5 Stars overall, and everyone has their favorites. In toto, you can expect a film with a higher Overall Star Rating to have more LF than one with a lower star rating, and most of the 4+ Star films/tracks are very good LF experiences.

**** Beginning of Bossobass's post here ****

Using Examples (not necessarily with correct time stamp, ratings, pics) of movies I've recently seen, here is where I'm at so far. This will be the template and all graphs and pics will be sized to fit the template. The top template will appear once at the beginning of the title and the bottom template will appear for each successive screen cap with the proper begin/end time stamp and begin/end pics for each scene.

First, for those who have asked me how to interpret the SpecLab waterfall graphs, here's a quick how-to:

The waterfall scrolls from top to bottom as the scene plays, so the beginning of the captured sceneis at the bottom of the waterfall, which is documented by the time stamp and a picture of the scenes beginning and, of course, the end of the scene is at the top of the graph, marked by the time stamp and a picture of the end of the scene.

Per Josh's suggestion, there will be 3 scenes for each movie. I may, from time to time, post additional scenes if a movie is exceptional or because someone has requested to see the content of a scene, but I'll post them separately to keep the archives of the films uniform.

If anyone would like to capture scenes in SL to help out with the workload, I've put Spectrumlab and my settings, as well as instructions for loading my settings into SL and the above pictured 'how-to-read-a-SL-waterfall-graph graphic on my site:

Make sure you note the beginning/end time stamp numbers and take a pic off your screen of the beginning and end. So, for each scene you need 2 pics, 2 time stamps and the waterfall graph. The movie pics are easy to get online at IMDB, which will also have the sound designer and mixer info.

Members who create SpecLab Caps can forward the caps to me and I'll fit them to the template and return them via e-mail in a file or host/post them.

Decide on how the rating will work, which graph (just the waterfall or the 3 graph cap), etc. from here.

Any Mac users, I'll be happy to forward the template for Omnigraffle because having someone to pick up the slack is always a good thing. Omnigraffle makes it very simple to size, place and export the template with everything needed to keep the graphs all the same size and resolution.

I would also prefer to keep the settings the same for all caps using my settings. They're found in a downloadable file on my site with SpecLab. Just download and then load the settings.INI file into SpecLab.

You'll have to make sure your volume settings and sound card settings are compatible/correct as well as setting the offset to match the input of your player or AVR to get the intensity of the colors correct and to insure against clipping. This beats the snot outta fighting the extremely steep SL learning curve.

Of course, I prefer my settings. This is because they are the result of years of experimentation to optimize them for the subwoofer range in a scroll speed that is meant to capture scenes, not huge time blocks. This makes a very accurate combination of resolution at the extreme low end in scenes (which is what everyone always asks for a graph of) that can be used to compare with other soundtracks at a glance.

Imagine if Josh formatted every set of data for his subwoofer tests differently, using different smoothing, distances, graph scales, etc. It would be infinitely more difficult to interpret the data. Because the data is consistent and presented in a consistent format, it's very easy to use for comparison within the body of work.

Anyway, this is a lot of spare time out the window. If done correctly and used in conjunction with Maxmercy's P2A (Peak To Average) graphs, also formatted consistently and in the future in a format that allows for instant comparison with other movies, this would become an extremely useful databass, to coin a term.

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Dave you make a really good point. Things need to be standardized and relative for easy comparison. Otherwise it becomes a nightmare to decipher. Sure there will be bitching about what the standard is or could or should be, but that is expected. As long as it all is the same at least easy comparisons can be made and things are relative.

I like the template from CITW above. IMO the spectrum window, input waveform and peak and long term graphs are all good information. It would be great to have the total average and peak results from each movie along with detailed captures from the top 3 or so select scenes.

Max I'm sorry but in order to keep posting here you are going to have to use some sort of snazzy avatar pic. You have 11 days and 22 hrs to get that rectified.

1

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Question: How much headroom do you leave on SpecLab caps? Because if for some reason a mixer shoves nearly full scale content into each of 7.1 channels, you could get a larger signal than the equivalent of a 0dBFS signal from the SW out.

According to Soho54's calculations, a 0dBFS LFE only signal should come only to 115dB, if any speaker is set to small and also has the same, coherently summing 0dBFS signal, it adds to this total, with a grand total with 7.1 channels being an impressive 125.13dB. I will from now on calibrate my peak/avg graphs to read -10dB on SpecLab with the -0.5dBFS signals available on Soho54's Audio Test DVD, so that means I'll be re-doing a few Peak/Avg graphs in order to be able to do apples/apples comparisons. Good thing I have Netflix by mail...

The template scheme for individual scenes is REALLY nice. Real nice.

I'll d/l your settings for SpecLab and check them out. I think you use a slightly slower scroll speed than I do, but you want whole scenes, not second-to-second variability like the Peak/Avg demands.

Anyone know a good program to be able to trace out the information on peak/avg graphs and import them to another graphing program for comparisons between tracks? Or a way to make a BMP file 'transparent' and overlay it over another?

JSS

PS - Josh, got the avatar sorted out.

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I'm a fan of the first posted template, Dave. Although one slight change I'd do: move the SPL scale off the actual graph somehow. At some point it will block some of the graphed content. Maybe have it right below where you have it saying 'Chapter 17'. Right in that spot. There should still be plenty of room for the scene specific details.

Still wondering about quantifying the rating system. If we are indeed rebooting the whole system and going for consistency, maybe we should not use the star system anymore. Simply thinking because it could be confusing for those regraphed scenes and movies that may get a higher or lower rating than before. Also, there really wasn't a whole lot of science in how we did it before. I'd say for the most part we got it right but those who didn't really skewed things up and then we got into all those back and forth spats regarding a simple star rating. Avengers certainly wasn't the first time it happened.

I'm very much pumped up to get back into the game and do some scene specific and maybe even do the P-A charts. I just don't know how to do it AND be consistent with someone else's settings. Over the years, I've mostly copied Dave's settings just by eyeing it and then recently he had posted some more specific info. All I need to know is what kind of gear I need to this because I won't be able to afford the awesome microphone B has to do his in room and I'm still stuck at 8-9hz extension in my room so maybe not a hot idea. I'd prefer to do all these digitally so to completely even the playing field and also accurately capture <5hz content when there is some.

Keep me in the loop. I'll be watching this thread.

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Great to be able to get in on a quantifiable ratings scale from the ground up.

Since the original intent of the concept was to provide a database of the bass content in movies, which can be browsed through to discern which movies have noteworthy bass (and are thus worth buying, or at least viewing), one of the things I was thinking was for the ratings system to have sub-categories. In maxmercy's example in the 1st post, this would fall under the A-assessment section.

eg.

- ULF: to differentiate between movies that go down to say single digit Hz,vs teens vs filtered at 30Hz etc.

- Amount: There could be a lot of bass in the movie, but it may all be above 30Hz etc.

Just bouncing some ideas around, as it would be good to be able to easily differentiate between movies like FOTP (Flight Of The Phoenix) and WOTW (War Of The Worlds) which might have 1 or 2 standout scenes in the enitre movie, but excellent demo scenes nonetheless, vs. movies like WOTT or TL (Tron:Legacy), that have lots of bass throughout the movie. It would help with movies that some of us personally haven't seen. I'd say that the P-A graps would be a good indicator of this, but if we're going to rate the movies and rank them, perhaps that would make it easier for someone browsing the list to differentiate between the types. Just a simple 5-star rating is too vague.

I would say that the eventual ratings, if we're going to group movies in any manner similar to a star rating system, is going to unavoidably be subjective, but perhaps if we could rate them something like:

2. I intend to to Peak/Average out to 200Hz, even if individual graphed scenes only have stuff out to 120Hz. I imagine your settings are best for 0-120Hz?

I have an idea to quantify the LF content, depending on whether or not I will be able to extract the data from the P/A graphs. With the new SpecLab version's way of graphing individual FFT bins, I may be able to use an autotracing program to get the data and comparison via REW or just Excel may be possible. If I am able to export to a vector drawing program, overlays comparing one film to another may be possible.

By adding up the areas under the peak/avg curves for a given freq range, we can literally compare one track to another numerically (0-10Hz, 10-20Hz, 20-30Hz, or the full 0-200Hz). Films/tracks with more average overall content will have more overall bass, films with high peak and lower averages will have less scenes with high signal strength. If we really want to get technical, we can do a 'loudness scale', by implementing ELC, but that may prove to be too difficult.

I will have a tutorial on how to do Peak/Avg graphs hopefully by this weekend.

JSS

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Question: How much headroom do you leave on SpecLab caps? Because if for some reason a mixer shoves nearly full scale content into each of 7.1 channels, you could get a larger signal than the equivalent of a 0dBFS signal from the SW out.

According to Soho54's calculations, a 0dBFS LFE only signal should come only to 115dB, if any speaker is set to small and also has the same, coherently summing 0dBFS signal, it adds to this total, with a grand total with 7.1 channels being an impressive 125.13dB. I will from now on calibrate my peak/avg graphs to read -10dB on SpecLab with the -0.5dBFS signals available on Soho54's Audio Test DVD, so that means I'll be re-doing a few Peak/Avg graphs in order to be able to do apples/apples comparisons. Good thing I have Netflix by mail...

The template scheme for individual scenes is REALLY nice. Real nice.

I'll d/l your settings for SpecLab and check them out. I think you use a slightly slower scroll speed than I do, but you want whole scenes, not second-to-second variability like the Peak/Avg demands.

Anyone know a good program to be able to trace out the information on peak/avg graphs and import them to another graphing program for comparisons between tracks? Or a way to make a BMP file 'transparent' and overlay it over another?

JSS

PS - Josh, got the avatar sorted out.

Since I mic and go direct, there is no universal setting for calibration. Spectrumlab has a calibration methodology:

To realize absolute voltage readings, level readings in dBuV, etc, the program needs to know the relation between input voltage and A/D converter value.

This is a rather complex calibration, IMO. I see no reason to go through that process for waterfall graphs.

The problem I have is that when I switch back and forth from digital feed from the player to the digital feed from the interface I have to re-calibrate, so instead I use the offset feature to reconcile the 2 different inputs.

I set the level from the interface with the right side amplitude bar. Headroom is dictated by the input from the interface. When I switch to the direct feed from the player, I adjust the "offset" to match the interface input by eye, which is accurate to within a couple of dB since I'm very familiar with the color scale and I'm comparing the exact same scene.

It's by no means absolutely accurate, but neither is anyone else's method, which is also done by eye, both methods being roughly the same accuracy, which is good enough, IMO.

The color intensity setting is also set by adjusting the "offset" option. I take a maximum peak from a scene like HTTYD Red Dragon crash scene and use it as the metric for maximum where any single frequency is approximately -5dBFS. Again, this is by no means absolutely accurate, but is based on viewing thousands of scenes compared to max digital RS meter readings, system reaction (VPL, clip limiter indicators vs output voltage readings) and all averaged in general. It gives me +5dB of "headroom" because I set my color scale range from -60dBFS to +5dBFS.

I don't believe it has ever been shown that there exists a scene in any soundtrack the scenario where 7 channels plus the .1 channel all simultaneously contain coherent 3-120 Hz content at maximum level, so I disregard the 125dB estimate. Of late, the only 2 scenes I would imagine might fit that scenario are the one pictured in the CITW I posted here and the Thor BR scene at the end of the battle with the Ice Giants when Odin shows up. In the latter, I saw a +10dB increase in level vs the DVD. I do not know what that's about. I did use 2 different players to compare that scene, but my system calibration should hold equal for both players, so I'm at a loss as to how the levels are different. IOW, can the mastering house raise the overall level after the disc is encoded, or how else would there be a difference?

Some people have reported that my settings, which are in the SpecLab preferred .INI format, do not appear to be the same as my settings. I use Windows 7, so I don't understand the problem, but am currently investigating it and should have suggestions to remedy any problems within a week.

Folks who download my settings should use a universal scene and post the resultant capture here, so that I'll know what any problem might be at a glance. This saves a go-zillion e-mails with graphs that need explanation before I might even begin to see a problem. Since most people have WOTW, the lightning strikes scene is the easiest for me to recognize immediately. Begin where Cruise and Fanning are indoors, Cruise is at the sliding glass doors and says, "Don't worry, lightning never strikes the same place twice" and end where they're under the table and Fanning says, "Why doesn't it stop?".

I'm a fan of the first posted template, Dave. Although one slight change I'd do: move the SPL scale off the actual graph somehow. At some point it will block some of the graphed content. Maybe have it right below where you have it saying 'Chapter 17'. Right in that spot. There should still be plenty of room for the scene specific details.

Still wondering about quantifying the rating system. If we are indeed rebooting the whole system and going for consistency, maybe we should not use the star system anymore. Simply thinking because it could be confusing for those regraphed scenes and movies that may get a higher or lower rating than before. Also, there really wasn't a whole lot of science in how we did it before. I'd say for the most part we got it right but those who didn't really skewed things up and then we got into all those back and forth spats regarding a simple star rating. Avengers certainly wasn't the first time it happened.

I'm very much pumped up to get back into the game and do some scene specific and maybe even do the P-A charts. I just don't know how to do it AND be consistent with someone else's settings. Over the years, I've mostly copied Dave's settings just by eyeing it and then recently he had posted some more specific info. All I need to know is what kind of gear I need to this because I won't be able to afford the awesome microphone B has to do his in room and I'm still stuck at 8-9hz extension in my room so maybe not a hot idea. I'd prefer to do all these digitally so to completely even the playing field and also accurately capture <5hz content when there is some.

Keep me in the loop. I'll be watching this thread.

Awesome suggestion, which is what I needed. I have far less time than I need to do all of this graphics and measuring stuff, so I'm really looking forward to guys like yourself to jump in and pick up the slack. I agree and it has always annoyed me when guys set the scale and time stamp info in the waterfall capture.

Here's the change:

As far as a rating system goes, I personally use a simple "BUY" or "DON'T BUY". It includes story, cast, script, visual effects and soundtrack. IOW, movies like Cloverfield do not cut muster. Sometimes, the sound will be good enough to outrank the other categories, but Cloverfield, for all its hype, is weak compared to the top soundtrack discs, so the other categories make it a "DON'T BUY".OTOH, WOTW is definitely a strong enough sound track to tip the scales.

So, whatever everyone decides as a rating system is fine with me. I really dislike subjective descriptions and rating systems. It's like describing the color red to a blind person and always leads to a dog-chasing-its-tail debate.

Tom Noussaine has that largest single body of eval results I'm aware of. He did all of it in-room, with the flaws that entailed (like his rooms +4dB peak at 32 Hz), but useful as a comparative tool in the end. Keith Yates is the only guy to ever use SpecLab and movie soundtrack scenes to compare subs, but he did so outdoors, GP with no sats (although he did mention a difference in overall dBSPL when FL/FR were added). I've always wished we could get a combination. Do the SL graphs of a global set of scenes indoors. Despite what the conventional wisdom says about all rooms being too different, I've found that to be largely a myth. It's not that hard to get a good enough (+/-) 3dB) FR in-room and if every sub is placed the same and the mic as well, the results would be hugely valuable.

Josh,

Why can't I drag an image code file onto this forum (the Mac unclunk method) vs copy/paste (the Windows clunk method), and what the heck is the default font/font size?

When I copy/paste, the font changes to the pasted font and I can't seem to find the default font on your font options drop down.

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Bosso, I have downloaded your speclab settings, and I will make some changes for peak/avg graphs, but overall, I like them. A few questions though: 1. Why Nuttall windowing? Wouldn't Hann or Gauss be a better compromise? 2. I intend to to Peak/Average out to 200Hz, even if individual graphed scenes only have stuff out to 120Hz. I imagine your settings are best for 0-120Hz? I have an idea to quantify the LF content, depending on whether or not I will be able to extract the data from the P/A graphs. With the new SpecLab version's way of graphing individual FFT bins, I may be able to use an autotracing program to get the data and comparison via REW or just Excel may be possible. If I am able to export to a vector drawing program, overlays comparing one film to another may be possible. By adding up the areas under the peak/avg curves for a given freq range, we can literally compare one track to another numerically (0-10Hz, 10-20Hz, 20-30Hz, or the full 0-200Hz). Films/tracks with more average overall content will have more overall bass, films with high peak and lower averages will have less scenes with high signal strength. If we really want to get technical, we can do a 'loudness scale', by implementing ELC, but that may prove to be too difficult. I will have a tutorial on how to do Peak/Avg graphs hopefully by this weekend. JSS

There are as many windowing choices as there are application for them. Unfortunately, they aren't all available in the SL drop down menu (such as Blackman'Harris, Blackman/Nuttall, etc.). Of the choices available, I chose Nuttall for it's increased dynamic range over Gauss.

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BTW back when I messed with SL last I was setting it up to clip at what would be the worst case scenario for 5.1 of 123.5dB (rounding up a bit) You will never see this signal but it ensures that you don't hit that one movie where all of a sudden you have to readjust everything. The way i went about this was to use the pink noise calibration from my receiver run into SL and knowing it was -48.5dB from the hottest signal that could be seen or 75dB. Just leave yourself 50dB of headroom from the pink noise and you know you will never run into clipping. You will have to factor in what your normal volume level for doing the graphs will be and adjust accordingly for that as well. Nobody listens at REF all the time except for maybe MK.

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I gotcha. The main discerning feature is the scale on the left for the freq response of each, very low spectral contamination on Nuttall, at the expense of a slightly lower resolution, but the resolution can be played with by FFT length and decimation. I'll mess with it this weekend.

Ricci,

I have always used the Soho54's Audio Test DVD's -0.5dBFS LFE tones to calibrate SpecLab, but some films have not clipped individual frequencies, but have clipped the amplitude graph, which I suspect is because of channel summation, not just LFE content, so I plan to use the same tones but have them only come to -10dB on my new peak/avg graphs. I am confident that I will be able to extract data from the screen caps, to really do some apples/apples comparos, much like your CEDIA best/worst output graphs.

What would be good bass ranges/categories? Here are some suggestions:

Sub-10Hz = Deep Infrasonic

10-20Hz = Infrasonic

20-30Hz = Very Deep Bass

30-40Hz = Deep Bass

40-50Hz = Bass

50-100Hz = Mid Bass

100-200Hz = Upper Bass

or all by octaves:

Sub-10Hz = Deep Infrasonic

10-20Hz = Infrasonic

20-40Hz = Bass

40-80Hz = MidBass

80-160Hz = UpperBass

We would be measuring total peak and average signal power for entire films in each range. One problem is my signal chain rolls off starting at 7Hz, and is 3dB down at 5Hz, and falls off the cliff below that, so my Sub-10Hz power ratings may not be as accurate, but will be good relative measurements. I may be able to compensate for that if there is a way to do a 'loopback calibration' type of thing in speclab....I'll research it.

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I gotcha. The main discerning feature is the scale on the left for the freq response of each, very low spectral contamination on Nuttall, at the expense of a slightly lower resolution, but the resolution can be played with by FFT length and decimation. I'll mess with it this weekend.

Ricci,

I have always used the Soho54's Audio Test DVD's -0.5dBFS LFE tones to calibrate SpecLab, but some films have not clipped individual frequencies, but have clipped the amplitude graph, which I suspect is because of channel summation, not just LFE content, so I plan to use the same tones but have them only come to -10dB on my new peak/avg graphs. I am confident that I will be able to extract data from the screen caps, to really do some apples/apples comparos, much like your CEDIA best/worst output graphs.

What would be good bass ranges/categories? Here are some suggestions:

Sub-10Hz = Deep Infrasonic

10-20Hz = Infrasonic

20-30Hz = Very Deep Bass

30-40Hz = Deep Bass

40-50Hz = Bass

50-100Hz = Mid Bass

100-200Hz = Upper Bass

or all by octaves:

Sub-10Hz = Deep Infrasonic

10-20Hz = Infrasonic

20-40Hz = Bass

40-80Hz = MidBass

80-160Hz = UpperBass

We would be measuring total peak and average signal power for entire films in each range. One problem is my signal chain rolls off starting at 7Hz, and is 3dB down at 5Hz, and falls off the cliff below that, so my Sub-10Hz power ratings may not be as accurate, but will be good relative measurements. I may be able to compensate for that if there is a way to do a 'loopback calibration' type of thing in speclab....I'll research it.

JSS

I like the 2nd metric, by octave.

How are you getting the feed into SpecLab? I'm assuming you're using an analog connection from the AVR to the sound card, thus the roll off.

Any way you can connect your player to the computer via USB? Or, if you have to suffer an analog stage roll off, if you have analog outs on your player you can connect that way and avoid the AVRs roll off, which I'm assuming has to be the offending roller.

My interface has digital coax in and my player has digital coax out. When I go direct, I bypass all analog stages and get the 1s and 0s all the way down. Comparing WOTW plane crash, digital feed vs mic'd version:

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Due to the cheapness of my BDP and sound card, My sound card cannot accept a digital in, and outside of stereo, there are no further analog outs on the BDP. I think that until a new BDP is purchased, the receiver's roll off may just have to be dealt with.

I was playing with the Nuttall windows and FFT settings yesterday evening, and I have come to an impasse:

1. Continue with FFT length of 1024 decimated by 48, which will give me single Hz resolution capability but that has a 1 second Window time, or:

2. Use an FFT length of 512 decimated by 48, which gives a resolution of 2Hz, but window time is halved, therefore it is better at graphing transient sounds like explosions.....faster rise time for each bin.

What do you guys think? For a peak/avg graph, I am leaning to the latter. I'll run some comparos on known scenes/trailers this weekend.

JSS

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I have always used the Soho54's Audio Test DVD's -0.5dBFS LFE tones to calibrate SpecLab, but some films have not clipped individual frequencies, but have clipped the amplitude graph, which I suspect is because of channel summation, not just LFE content, so I plan to use the same tones but have them only come to -10dB on my new peak/avg graphs. I am confident that I will be able to extract data from the screen caps, to really do some apples/apples comparos, much like your CEDIA best/worst output graphs.

or all by octaves:

Sub-10Hz = Deep Infrasonic

10-20Hz = Infrasonic

20-40Hz = Bass

40-80Hz = MidBass

80-160Hz = UpperBass

JSS

That sounds like it should work. I am doing essentially the same thing. I just don't have Soho's disc. Matter of fact I haven't heard from him in a long time now.

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I am new around here but I would like to contribute to this thread. I have SL installed with the .INI file from Bosso...

I have an old Dell XPS400 computer with Windows XP Media Center installed with the standard internal sound card. I have an old Toshiba DVD player with 5.1 analog outs as well as an optical & coaxial digital outputs. I would need to upgrade my sound card to take advantage of the digital output from the DVD player....any suggestions?

OK, here is my first shot at this. Here is the scene that Bosso wants us to use from WOTW:

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Due to the cheapness of my BDP and sound card, My sound card cannot accept a digital in, and outside of stereo, there are no further analog outs on the BDP. I think that until a new BDP is purchased, the receiver's roll off may just have to be dealt with.

I was playing with the Nuttall windows and FFT settings yesterday evening, and I have come to an impasse:

1. Continue with FFT length of 1024 decimated by 48, which will give me single Hz resolution capability but that has a 1 second Window time, or:

2. Use an FFT length of 512 decimated by 48, which gives a resolution of 2Hz, but window time is halved, therefore it is better at graphing transient sounds like explosions.....faster rise time for each bin.

What do you guys think? For a peak/avg graph, I am leaning to the latter. I'll run some comparos on known scenes/trailers this weekend.

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SpecLab accounts for the decimation at the I/O stage in the FFT Settings dialogue box, and updates with proper bin size and freq range.

I say we have a few different star ratings, with an overall rating given last.

Overall LF Content Star Rating is an average of several different 5/5 star possible ratings:

A. Level

B. Extension

C. Execution/Appropriateness/Use of LF

Then a final 'buy' or 'no buy' rating given with everything else taken into acount, like how good the film was, rewatchability, etc.

The objective ratings (if I can get them to work this weekend) may also play a part.

I intend to do Peak v Avg graphs and hopefully overall LF Power as well as LF Power Per Octave for each film rated. The ratings will probably be a mix of subjective and objective for an overall star rating.

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SpecLab accounts for the decimation at the I/O stage in the FFT Settings dialogue box, and updates with proper bin size and freq range.

I understand, but I was just saying that the I/O decimation still has to be entered manually or there's nothing to account for.

I say we have a few different star ratings, with an overall rating given last.

Overall LF Content Star Rating is an average of several different 5/5 star possible ratings:

A. Level

B. Extension

C. Execution/Appropriateness/Use of LF

Then a final 'buy' or 'no buy' rating given with everything else taken into acount, like how good the film was, rewatchability, etc.

The objective ratings (if I can get them to work this weekend) may also play a part.

I intend to do Peak v Avg graphs and hopefully overall LF Power as well as LF Power Per Octave for each film rated. The ratings will probably be a mix of subjective and objective for an overall star rating.

Any other suggestions?

JSS

No, is perfect. :^)

3

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Objectively it would be nice if the ratings could involve the peak and average hold graph. Average would give a look at how much total bass is in the movie and the peak gives a look at how loud it maxes out at. Extension should be looked at as well. Also the best 3 or 4 demo type parts should be charted.

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What will happen is Bosso will provide the specific demo scene caps, I will provide peak/avg, and I will tinker today to see if I can actually extract data from it, to be able to calculate peak and average power per octave, and the ratings will come from both. Note that subjectivity is still a part of the ratings, as one of the 5-star measures is subjective, as well as the final 'buy' or 'no buy' rating. I am going to rearrange the first post to show this.

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We will post tutorials on how to generate these graphs so that more folks can contribute to the thread.

Hi maxmercy, count me in to help contribute. I want to thank Bosso for taking the time in helping me get set-up with SL and being patient with all my e-mails. I am getting closer and attached is my latest graph from WOTW that bosso suggested.

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I'm bringing this one here (have already e-mailed you on this) because it's a head scratcher for sure:

I put my digital copy of this scene up in Omnigraffle with your latest posted version. I tried to reconsile the 2 graphs for a long while and could not do it. For example, you show a lot of content in the 60 Hz area that just isn't on the disc.

Finally, my brain caught it. I stretched my graph until just my 0-30 Hz lined up with your 0-120 Hz frequency scale and there it was, a perfect match (although my graph is distorted to a large degree):

Your graph is on top, my version is on the bottom and the severely stretched version is in the middle.

I have no clue as to how your SL frequency scale is so far off. I suggested in e-mail that you change your frequency scale (top left corner of the display) to (I think) 0-450 Hz. I would actually like to see 0-480 Hz (reasoning that if your 0-120 Hz is actually 0-30 Hz, then if you quadruple your scale to 480 Hz, you may actually capture 0-120 Hz).

Windows (ugh)

I also suggested you reboot your computer and try the graph again.

If you can post the expanded FR scaled graph here, that would be great...